This invention relates to an electric distribution box for connecting and distributing a power circuit collectively to a load circuit such as a controller via relays and a method of assembling the same.
One known related electric distribution box includes an upper cover, an intermediate cover and a lower cover which jointly form a receiving space within which electrical parts are received (see, for example, JP-A-11-027829 (Page 3, FIG. 2)).
As shown in FIG. 9, the electric distribution box 100, disclosed in JP-A-11-027829, includes the upper cover 101, the intermediate cover 102 and the lower cover 103 (each of which is made of a synthetic resin) which jointly form a box-like connection box within which a wiring board 104, a bus bar circuit board 105, a printed circuit board 106, connectors 107 and 108, a fuse mounting portion 109 and a relay mounting portion 110 are received.
The wiring board 104 includes an insulating board, and a plurality of wires 111 are installed on this insulating board, and are connected to press-contacting portions formed respectively at one ends of L-shaped terminals 112. Tab-like contact portions, formed respectively at the other ends of the L-shaped terminals 112, project into the interior of a connector housing to form the connector 107.
The bus bar circuit 105 includes an insulating board on which a plurality of bus bars 113 are installed, and terminal portions of the bus bars 113 are disposed within the fuse mounting portion 109. The printed circuit board 106 includes an insulating board having printed circuits of predetermined shapes formed thereon. The printed circuit board 106 and the wiring board 104 are connected together by long terminals 114. L-shaped terminals 115, connected to the printed circuit board 106, project into the interior of the connector 108. The connectors 107 and 108 and the fuse mounting portion 109 project outwardly from the intermediate cover 102. The printed circuit board 106 is fixed to the intermediate cover 102 and the lower cover 103 by a mounting plate 116 and screws 117.
In the electric distribution box described in JP-A-11-027829, however, the various component parts, including the wiring board 104, the circuit boards 105 and 106, the connectors 107 and 108, the fuse mounting portion 109 and the relay mounting portion 110, are received within the receiving space formed by the covers 101, 102 and 103. Therefore, there has been encountered a problem that a dead space is liable to be formed within the receiving space formed by the covers, so that the size of the electric distribution box increases, and also there has been encountered another problem that it is difficult to connect circuits at a high density.
Cumbersome joining technique (such as soldering) is required for electrically connecting the circuit boards 105 and 106, the connectors 107 and 108, the fuse mounting portion 109, the relay mounting portion 110 and so on to one anther so as to form circuits, and this has invited a problem that the time and labor required for the assembling operation, as well as the cost of the assembling operation, can not be reduced.